The present invention relates to a eutectic bond and a method of Gold/Silicon eutectic bonding of Cadmium Telluride to a Sapphire wafer. And, more particularly to eutectic bonding which achieves precise parallelism and tailors thermal expansion coefficients through the control of Gold and Silicon layer thickness.
Gold/Silicon (Au/Si) bonding is widely used in the semiconductor industry to attach Silicon die to Gold-plated packages. In those applications the parallelism of the Silicon die to the package is not a critical requirement. For that reason neither the amount of the Silicon nor the amount of the Gold used in the bonding process is controlled.
Typically, only a minimum amount of Gold is required to form the eutectic layer between the Silicon die and the package.